This invention relates to grain wagons with unloading conveyors or augers, for example, of the general type disclosed in U.S. Pat. No. 5,340,265 which issued to the assignee of the present invention. A number of the references cited in this patent disclose side discharge wagons, for example, as disclosed in U.S. Pat. No. 3,265,253. Such wagons are commonly used for hauling or transporting grain, feed, dry fertilizer or other granular material, and include a gravity discharge container or hopper having a gate-controlled discharge opening within an inclined side wall of the hopper at the bottom of the hopper. The material flows from the hopper through the opening and into a side mounted open top receiving box.
An elongated auger unit includes a tubular housing or conduit enclosing a hydraulically driven auger, and a lower inlet portion of the auger unit is inserted into the material receiving box. As shown in U.S. Pat. No. 3,265,253, the material receiving box is attached to the lower end portion of the auger conduit and is pivotally connected to the bottom of the hopper adjacent the side wall outlet. Another form of unloading auger unit is disclosed in U.S. Pats. No. 3,391,778. In this patent, the lower end portion of the auger conduit is connected to an upwardly projecting and part-spherical ball member which seats within a mating part-spherical annular socket projecting downwardly from a material receiving box. The part-spherical ball and socket support for the auger unit permits the unit to be rotated on a generally vertical axis and also tilted in a vertical plane extending through the axis. However, the part-spherical ball and socket support for the auger unit is difficult and expensive to construct, especially to obtain precise matching of the ball and socket. The mating part-spherical ball and socket arrangement also presents a problem when granular dry fertilizer seeps into any gaps between the ball and socket and then compacts and restricts movement. This causes binding of the ball to the socket and prevents free movement or swiveling of the auger unit.